You return from the open sea. you see a red lighted buoy with the number 6. what should you do?

The right thing to do is to PASS BY THE BUOY WHILE KEEPING IT ON YOUR RIGHT HAND SIDE. Buoy is an example of aids to navigation. In the United States, the lateral system is used, which involves marking the sides of the channels. When a vessel enter a smaller body of water from a large one, that means the vessel is returning, it is expected that the vessel leave the red buoy to starboard when returning. 

From my calculation, i got 3.655moles